Killer cell immunoglobulin-like receptor (KIR) gene contents: Are they associated with cervical cancer?

Killer cell immunoglobulin-like receptors (KIRs) are required for natural killer cell function against virus-infected cells or tumor cells. KIR gene content polymorphisms in Indian women with cervical cancer (CaCx) remain unexplored. Hence, we analyzed the frequencies of KIR genes, KIR haplotypes, and Bx subsets to draw their association with CaCx. The polymerase chain reaction-sequence-specific primer method was used for KIR genotyping in three groups of women: healthy controls (n = 114), women with human papillomavirus (HPV) infection (n = 70), and women with CaCx (n = 120). The results showed that the frequency of KIR2DS5 was significantly higher in women with CaCx compared to women with HPV infection (p = 0.02) and healthy controls (p = 0.01). Whereas the frequency of KIR2DL5B was significantly higher in healthy controls than in women with HPV infection (p = 0.02). The total number of activating KIR genes was higher in women with CaCx than in healthy controls (p = 0.006), indicating their positive association with CaCx. Moreover, the C4T4 subset was higher in women with CaCx than in women with HPV infection, though not significant. In conclusion, our findings highlight KIR2DS5, the C4T4 subset, and activating KIR genes are susceptible factors or positively associated with CaCx. Besides KIR2DL5B, this study also reported for the first time significantly high frequency of KIR2DL1 in healthy controls, indicating its possible protective association against CaCx. Further, significantly high frequency of KIR2DL3 observed in HPV-infected women might be also a promising biomarker for viral infections. Thus, the study confirms the association of KIR genes with cervical cancer in women with HPV infection.

Human Papillomavirus E6/E7 oncogene transcripts as biomarkers for the early detection of cervical cancer.

Cancer of the cervix uteri is the fourth most common cancer worldwide with a high mortality rate. Due to limitations of the existing methods, alternative methods for triage are needed for early detection of cervical cancer precursors before progression to high-grade disease. The aim of this study was to evaluate human papillomavirus (HPV) E6/E7 oncogene expression as markers for early identification of cervical cancer risk in women with minor cytological abnormalities and in those with negative cytology. The detection of HPV was done using PCR and confirmed by southern hybridization. The high-risk (HR) and low-risk HPV types were identified by HPV typing. HPV DNA-positive patients were further tested for markers of oncogene expression by real-time PCR. Out of the women screened, 54/512 (10.54%) women tested positive for HPV infection. HR HPV DNA was found in 32/485 (6.60%) women with normal cytology (Pap negative) and 22/27 (81.5%) atypical squamous cells of undetermined significance/low-grade intraepithelial lesion cases. HR HPV E6/E7 oncogene transcripts were detected in 36/512 (7.03%) patients. The positivity rate of E6/E7 messenger RNA (mRNA) was 2.48% (12/485) in normal cervical cytology group and 88.9% (24/27) in abnormal cervical cytology group. The HPV E6/E7 mRNA test sensitivity was found to be 88.89% and specificity was 97.53%. In comparison, the sensitivity of the HPV DNA test was found to be 81.48% and specificity was 93.40%. In conclusion, E6 and E7 transcripts could provide a sensitive, early predictor of cervical cancer risk in women with normal cytology and minor cytological alterations.

Human leukocyte antigen B distribution in HIV discordant cohort from India.

Limited reports are available on association of HLA-B with HIV infection from India, a home to the third largest population of HIV infected people in the world. This emphasizes the need to have more information specifically the genetic constitution of HIV serodiscordant couples (DCs), where one spouse is seropositive (HSP) while the other remains seronegative (HSN) even after repeated exposure. Hence, aim of this study was to document association of HLA-B with HIV infection in DCs living in Mumbai, India. A cohort was designed to enroll DCs attending the ICTC/Shakti Clinic of KEM Hospital, Mumbai. A group of unexposed volunteers were also enrolled as healthy controls (HC). HLA-B alleles were typed using sequence-specific oligonucleotide probes. Allele frequency comparison was done using 2×2 contingency tables. Results were considered significant, when p<0.05 with two-tailed Fisher's exact test. At HLA-B locus, the frequencies of HLA-B*40;-B*35;-B*07;-B*15;-B*51;-B*44;-B*52;-B*37 and -B*57 were found in decreasing order in the population. Frequency of HLA-B*35 allele was significantly higher (HSP vs HSN; p<0.02 and HSP vs HC; p<0.04) in HSP. HLA-B*40 (HSN vs HSP; p<0.01 and HC vs HSP; p<0.01) and HLA-B*18 (HSN vs HSP; p<0.02) were significantly associated with HSN. Both HSN and HC had similar HLA-B*35 and -B*40 allele frequency. HLA-B*57 allele was observed in 15 individuals (3.69%). However, HLA-B*57:01 which is known to be associated with adverse reactions against Abacavir was observed in 7 of them. HLA-B*39 was observed exclusively in HSP. Our observation in DCs confirmed the association of HLA-B*35 with susceptibility while HLA-B*40 (specifically *B40:06), -B*18 with protection. These identified alleles can be used as possible marker associated with HIV transmission. In India, HLA screening is not carried out before initiation of HIV treatment. However, the presence of HLA-B*57:01 in the population emphasizes the importance of such screening to predict/avoid Abacavir hypersensitivity.

Human Papillomavirus infection in asymptomatic population.

OBJECTIVES: The present study aimed to evaluate type specific Human Papillomavirus (HPV) strains in women with different clinical manifestations but with normal cervical cytology, attending a gynecology out patient clinic and HPV infection in males attending a private pathology laboratory for routine check up in Mumbai. METHODS: Cervical swab specimens from 470 women with normal cervical cytology as detected by Pap were used for detection and typing of HPV by PCR, southern blotting and sequencing. In 104 males, 30 ml of first void/random urine specimens were used for HPV screening. RESULTS: Thirty-eight women (8.1%) tested positive for HPV. HPV 16, 18, 6, 11 and mixed infection was observed in 26.3%, 10.5%, 36.8%, 5.2% and 15.8% of these infected women, respectively, while 36.8% had other HPV types, indicating high rate of high-risk HPV types 16/18. Among the 104 males, 12 (11.5%) had HPV infection, 50% (n=6) of them were below 30 years. Nine of them were married and three were unmarried. CONCLUSIONS: The present study revealed presence of high risk HPV infection in women with normal cervical cytology. This is the first report from the Western region of India on HPV infection in males using urine specimen.