Immunohistochemical Expression of p16 and p53 as Prognostic Indicator in Oral Squamous Cell Carcinoma: A Cross-sectional Study

Introduction: Head and Neck Squamous Cell Carcinoma (HNSCC) is the sixth most common cancer globally and the seventh most common cause of cancer-related mortality. Tobacco use, alcohol consumption, and Human Papillomavirus (HPV) infection are prominent risk factors for HNSCC. HPVpositive Oral Squamous Cell Carcinoma (OSCC) differs from HPV-negative OSCC in terms of risk factors, preferential site of origin, age, histomorphological features, molecular genetic alterations, and prognosis. The prominent basaloid morphology and lobular growth of OSCCs are associated with p16 positivity and p53 negativity, respectively. Aim: To establish the immunohistochemical expression of p16 (p16INK4a) and p53 in OSCC and to assess their relationship with specific histomorphological features, in the form of solid growth of cells in a lobular configuration, small crowded cells with scant cytoplasm, dark hyperchromatic nuclei without nucleoli. Materials and Methods: The cross-sectional study involved fifty cases of OSCC over a two-year period from January 2017 to January 2019 at Army Hospital (R and R) Delhi Cantt. The intensity of p16 and p53 protein expression was graded as follows: no staining (0), weak staining (1), moderate staining (2), and strong staining (3). The proportion/percentage of staining for p16 and p53 protein expression was calculated as follows: 1-4% (1), 5-19% (2), 20-39% (3), 40-59% (4), 60-79% (5), and 80-100% (6) cells stained. A quick score of 0-1 (negative), 2-3 (weak positive), 4-5 (moderate positive), and >6 (strong positive) was assessed. Cross tables were generated and the Chi-square test was used for testing associations. The Statistical Software for Data Science (STATA)-14 was used for statistical analysis. Results: A total of 50 cases of OSCC were analysed for histomorphological features and immunohistochemical patterns of p16 and p53. The age distribution showed that 8 (16%), 9 (18%), 18 (36%), 13 (26%), and 2 (4%) of the patients were in the age groups of 31-40 years, 41-50 years, 51-60 years, 61-70 years, and above 70 years, respectively. The gender distribution noted 42 (84%) males and 8 (16%) females. Genital and nongenital mucosa are usually involved by HPV subtypes 6, 11, 16, 18, and 16, 18, 11, 13, 2, respectively. HPV-16 has been demonstrated in 90-95% of all HPV-positive HNSCC cases, followed by HPV-18, HPV-31, and HPV-33. p53 is considered the guardian of the genome and controls the expression and activity of proteins involved in cell cycle regulation, DNA repair, cellular senescence, and apoptosis. More than 50% of all primary HNSCC exhibit p53 mutation. Conclusion: A significant correlation was observed between age, dysplasia, keratinisation, basaloid morphology versus p16 expression, and lobular growth, histological grade versus p53. An inverse relationship between p16 and p53 expressions was observed. The immunohistochemical expression of p16 as an immunohistochemical marker of HPV, along with p53, is recommended. Due to the constraint of the study period, the survival of the patients could not be assessed in correlation with p16 and p53 expression

Genetic diversity of Leishmania donovani that causes cutaneous leishmaniasis in Sri Lanka: a cross sectional study with regional comparisons.

BackgroundLeishmania donovani is the etiological agent of visceral leishmaniasis (VL) in the Indian subcontinent. However, it is also known to cause cutaneous leishmaniasis (CL) in Sri Lanka. Sri Lankan L. donovani differs from other L. donovani strains, both at the molecular and biochemical level. To investigate the different species or strain-specific differences of L. donovani in Sri Lanka we evaluated sequence variation of the kinetoplastid DNA (kDNA).MethodsParasites isolated from skin lesions of 34 CL patients and bone marrow aspirates from 4 VL patients were genotyped using the kDNA minicircle PCR analysis. A total of 301 minicircle sequences that included sequences from Sri Lanka, India, Nepal and six reference species of Leishmania were analyzed.ResultsHaplotype diversity of Sri Lankan isolates were high (H d  = 0.757) with strong inter-geographical genetic differentiation (F ST  > 0.25). In this study, L. donovani isolates clustered according to their geographic origin, while Sri Lankan isolates formed a separate cluster and were clearly distinct from other Leishmania species. Within the Sri Lankan group, there were three distinct sub-clusters formed, from CL patients who responded to standard antimony therapy, CL patients who responded poorly to antimony therapy and from VL patients. There was no specific clustering of sequences based on geographical origin within Sri Lanka.ConclusionThis study reveals high levels of haplotype diversity of L. donovani in Sri Lanka with a distinct genetic association with clinically relevant phenotypic characteristics. The use of genetic tools to identify clinically relevant features of Leishmania parasites has important therapeutic implications for leishmaniasis

Additional file 1: of Genetic diversity of Leishmania donovani that causes cutaneous leishmaniasis in Sri Lanka: a cross sectional study with regional comparisons

Multiple sequence alignment. Multiple sequence alignment of the Sri Lankan, Indian and Nepalese isolates along with the reference sequences using CLUSTAL 2.1 multiple sequence alignment. Dashes(−) represent gaps introduced to optimize alignment. Asteriks (*) represent consensus nucleotides in the sequence. Lb(P):L. braziliensis [Peru] (Skin);Ld(DD8)/Ld(IN):L. donovani [India] (Bone marrow); Li(SP):L. infantum [Spain] (Unknown); Lm(A1):L. major [Libya]; Lt(TK):L. tropica [Turkey] (Skin); Lam: L. amazonenis (Skin); Li(TK):L. infantum [Turkey] (Spleen); SL-VL (52–55): VL Sri Lankan isolate (Bone marrow); SL_CL-S:Leishmania CL Sri Lankan isolate (Skin); SL_CL-DR:Leishmania CL Sri Lankan that failed to respond to antimonial drugs (Skin); IN-VL: L. donovani [India] (Bone marrow); IN-PKDL: Leishmania from post-kala azar dermal leishmaniasis (PKDL) [India] (Skin); NP-VL: Leishmania VL Nepalian isolate (Bone marrow); NP-PKDL:Leishmania cause PKDL [Nepal] (Skin). (DOCX 25 kb

Root metabolic response of rice (Oryza sativa L.) genotypes with contrasting tolerance to zinc deficiency and bicarbonate excess

Plants are routinely subjected to multiple environmental stresses that constrain growth. Zinc (Zn) deficiency and high bicarbonate are two examples that co-occur in many soils used for rice production. Here, the utility of metabolomics in diagnosing the effect of each stress alone and in combination on rice root function is demonstrated, with potential stress tolerance indicators identified through the use of contrasting genotypes. Responses to the dual stress of combined Zn deficiency and bicarbonate excess included greater root solute leakage, reduced dry matter production, lower monosaccharide accumulation and increased concentrations of hydrogen peroxide, phenolics, peroxidase and N-rich metabolites in roots. Both hydrogen peroxide concentration and root solute leakage were correlated with higher levels of citrate, allantoin and stigmasterol. Zn stress resulted in lower levels of the tricarboxylic acid (TCA) cycle intermediate succinate and the aromatic amino acid tyrosine. Bicarbonate stress reduced shoot iron (Fe) concentrations, which was reflected by lower Fe-dependent ascorbate peroxidase activity. Bicarbonate stress also favoured the accumulation of the TCA cycle intermediates malate, fumarate and succinate, along with the non-polar amino acid tyrosine. Genotypic differentiation revealed constitutively higher levels of d-gluconate, 2-oxoglutarate and two unidentified compounds in the Zn-efficient line RIL46 than the Zn-inefficient cultivar IR74, suggesting a possible role for these metabolites in overcoming oxidative stress or improving metal re-distribution